The aim of this study was to determine the effect of pre-sowing helium-neon (He-Ne) laser irradiation of pea seeds on changes in seed biochemical processes, germination rate, seedling emergence, growth rate, and yield. The first experimental factor was exposure to laser radiation: D0 - no irradiation, D3 - three exposures, D5 - five exposures, and the harvest dates were the second factor. Pre-sowing treatment of pea seeds with He-Ne laser light increased the concentrations of amylolytic enzymes and the content of indole-3-acetic acid (IAA) in pea seeds and seedlings. The exposure of seeds to He-Ne laser light improved the germination rate and uniformity and modified growth stages, which caused acceleration of flowering and ripening of pea plants. Laser light stimulation improved the morphological characteristics of plants by increasing plant height and leaf surface area. Irradiation improved the yield of vegetative and reproductive organs of pea, although the effects varied at the different growth stages. The increase in the seed yield resulted from a higher number of pods and seeds per plant, whereas no significant changes were observed in the number of seeds per pod. Both radiation doses exerted similarly stimulating effects on pea growth, development, and yield.

The aim of this paper was to determine the changes in some biochemical and physiological processes, which occurred in seeds and seedlings of faba bean and to evaluate the germination dynamics and plant emergence after pre-sowing seeds treatment with a magnetic field. The study was carried out on Petri dishes in climatic chambers of the company HERAEUS (Germany). Each plate was lined with filter paper and 80 seeds of faba bean were sown. The paper was sprayed with the same amount of distilled water in each plate. Treatment of seeds significantly increased the activity of amylolytic enzymes in faba bean seeds and seedlings. The greatest differentiation in enzymatic activity between stimulated and nontreated seeds was noted after 96 h from the time of sowing. Seeds treated with the magnetic field showed greater dynamics of weight at the time of imbibition than nontreated seeds. Treating of seeds with a magnetic field considerably increased the amount of indole-3-acetic acid and gibberellic acid in germinating seeds, above-ground parts and in roots of faba bean seedlings. The pre-sowing treatment with a magnetic field had favorable effects on the growth and development of seedlings.

The aim of the presented studies was to evaluate the magnetic field (MF) effect on changes in some enzymes and phytohormones that takes place in the process of seed germination and growth of seedlings. Studies were led in the climatic chambers HERAEUS, on Petri dishes during six consecutive days. Pea seeds were divided into three groups from which one was the control (without stimulation) and two were treated with different doses of magnetic field (30 and 85 mT, respectively). Contents of amylolytic enzymes (AE) and phytohormones were determined at seven terms (0; 24; 48; 72; 96; 120 and 144 h) after placing them on the dishes. A favorable effect of seed stimulation with MF was found on the biochemical processes in the germinating seeds and pea seedlings. The size of changes in enzyme concentration was dependent mainly on the advancement of germination process (i.e., on length of time in which the seeds were on the dishes) and the MF treatment. The use of MF also had an effect on the increase in hormone content in the seeds and organs of seedlings, but values from objects treated with different doses did not differ significantly.

Leptosphaeria maculans and L. biglobosa are fungal pathogens able to cause allergic reactions in humans and infect plants of Brassica species. The rate of their development and subsequent spore release depend on weather conditions. The aim of this paper was to pinpoint the exact meteorological conditions triggering the release of L. maculans and L. biglobosa ascospores in central and eastern Poland. Multiple regressions indicated that the frequency and amount of rainfall over short periods were important in mediating spore release. The first ascospore event depended mainly on the number of rainy days during the first 10 days of July and the cumulative precipitation during July and September. The most important variables for maximum spore release were cumulative rainfall in the beginning of July and the end of September, as well as the number of days with precipitation events in the first 10 days of August. The results highlighted for the first time the importance of the days preceding the collection of oilseed rape plants from the field. Higher moisture content of senescing but still living stems play a crucial role in the early start of the ascospore season and the maximum release of ascospores. This was not yet considered to date.